The present Assignee's French patent application No. 82 08 516 filed May 14, 1982 (U.S. Ser. No. 946,801) describes a power supply circuit for a wave generator in a pulse radar comprising a primary winding connected, in series with an electronic power switch, to the terminals of a filtered and rectified on board voltage source, said switch being controlled at the recurrence frequency of the pulses produced by the radar or at a frequency which is a multiple thereof. The primary winding is wound about a magnetic component core having a plurality of secondary windings wound thereon, with each secondary winding being connected in series with a diode and filter capacitor. These capacitors are themselves connected in series.
A plurality of transformers of this type may be stacked in series, with additional capacitors being connected in parallel with the series circuit formed by each primary winding in order to sum the secondary voltages from each transformer at the very high tension output terminals of the power supply.
Unfortunately, connecting such transformers in series in order to power the various electrodes of a microwave tube, which electrodes consume different powers, would require the power seen from the primary of each transformer to be different from one transformer to another, thereby unbalancing the loads seen by the primaries of said transformers and thus preventing the circuit from operating properly.
In French patent application No. 86 14336 filed Oct. 15, 1986, (U.S. Ser. No. 07/076,356) the Assignee has also proposed a high frequency power supply including a voltage source connected via a power switch to two primary windings which are connected in parallel and which are magnetically coupled with a magnetic circuit which is generally rectangular in shape. Pairs of secondary windings are printed on insulating substrates which are separated by insulating inserts, and have the cores of the magnetic circuit passing perpendicularly through the holes of the insulating substrates and inserts.
Such a circuit provides excellent electrical performance, is as compact as possible, and is easily manufactured industrially. However, putting a plurality of transformers of this type is series in order to power the electrodes of a microwave tube which consume different powers inevitably leads to an unbalance between the loads seen by the primaries of said transformers.
The aim of the invention is to provide a solution to this problem, by providing a circuit enabling a plurality of microwave tube electrodes consuming different powers to be powered with very high voltage without giving rise to unbalance in the loads seen by the circuit primary.